importn7bits.tdf

可以受上位机控制的通过fpga的视频信号发生器程序

TITLE "Byte-serial import of N*7 bits";

%
program imports N*7 bits of data through one 8-bit IO expander for frantic

low-to-high MSB = clock highword (contains 7-bits address)
high-to-low MSB = clock lowword (contains 7-bits data) + clockout
updated from "import14bits.tdf" (by Eric Funke 16th march 2000)
Age van Dalfsen, 29th March 2000

updated to accomodate 7 more bits. Eric Funke, 10th august 2000
updated to accomodate 14 more bits. Eric Funke, 18th september 2000

At this moment "address" can be 0..4, therefore giving 7 * 7bits output.


%

CONSTANT NDELAY = 20;


SUBDESIGN importN7bits
(
clock					:	INPUT;
data[7..0]				:	INPUT;
Xout[69..0]				:	OUTPUT;--27--35
)

VARIABLE

Xoutbuf0[6..0]				:	DFFE;
Xoutbuf1[6..0]				:	DFFE;
Xoutbuf2[6..0]				:	DFFE;
Xoutbuf3[6..0]				:	DFFE;
Xoutbuf4[6..0]				:	DFFE;
Xoutbuf5[6..0]				:	DFFE;
Xoutbuf6[6..0]				:	DFFE;
Xoutbuf7[6..0]              :	DFFE;
Xoutbuf8[6..0]              :	DFFE;
Xoutbuf9[6..0]              :	DFFE;
lowword[6..0],highword[6..0]		:	DFFE;
MSB_delay[NDELAY-1..0]				:	DFF;
MSB_transup,MSB_transdown		:	DFF;
MSB_transdown_delay			:	DFF;

BEGIN

MSB_delay0.d = data7;
MSB_delay0.clk = clock;

MSB_delay[NDELAY-1..1].d = MSB_delay[NDELAY-2..0].q;
MSB_delay[].clk = clock;

MSB_transup.clk = clock;
MSB_transup.d = ((MSB_delay[NDELAY-2].q) AND (NOT MSB_delay[NDELAY-1].q));

MSB_transdown.clk = clock;
MSB_transdown.d = ((NOT MSB_delay[NDELAY-2].q) AND (MSB_delay[NDELAY-1].q));

MSB_transdown_delay.clk = clock;
MSB_transdown_delay.d = MSB_transdown.q;

highword[].d = data[6..0];
highword[].clk = clock;
highword[].ena = MSB_transup.q;

lowword[].d = data[6..0];
lowword[].clk = clock;
lowword[].ena = MSB_transdown.q;

Xoutbuf0[].clk = clock;
Xoutbuf1[].clk = clock;
Xoutbuf2[].clk = clock;
Xoutbuf3[].clk = clock;
Xoutbuf4[].clk = clock;
Xoutbuf5[].clk = clock;
Xoutbuf6[].clk = clock;
Xoutbuf7[].clk = clock;
Xoutbuf8[].clk = clock;
Xoutbuf9[].clk = clock;

CASE (highword[].q) IS

WHEN 0 =>
	Xoutbuf0[].d = lowword[].q;
	Xoutbuf0[].ena = MSB_transdown_delay.q;
WHEN 1 =>
	Xoutbuf1[].d = lowword[].q;
	Xoutbuf1[].ena = MSB_transdown_delay.q;
WHEN 2 =>
	Xoutbuf2[].d = lowword[].q;
	Xoutbuf2[].ena = MSB_transdown_delay.q;
WHEN 3 =>
	Xoutbuf3[].d = lowword[].q;
	Xoutbuf3[].ena = MSB_transdown_delay.q;
WHEN 4 =>
	Xoutbuf4[].d = lowword[].q;
	Xoutbuf4[].ena = MSB_transdown_delay.q;
WHEN 5 =>
	Xoutbuf5[].d = lowword[].q;
	Xoutbuf5[].ena = MSB_transdown_delay.q;
WHEN 6 =>
	Xoutbuf6[].d = lowword[].q;
	Xoutbuf6[].ena = MSB_transdown_delay.q;
WHEN 7 =>
	Xoutbuf7[].d = lowword[].q;
	Xoutbuf7[].ena = MSB_transdown_delay.q;	
	WHEN 8 =>
	Xoutbuf8[].d = lowword[].q;
	Xoutbuf8[].ena = MSB_transdown_delay.q;	
	WHEN 9 =>
	Xoutbuf9[].d = lowword[].q;
	Xoutbuf9[].ena = MSB_transdown_delay.q;	
END CASE;

Xout[69..63]	= Xoutbuf9[].q;
Xout[62..56]	= Xoutbuf8[].q;
Xout[55..49]	= Xoutbuf7[].q;
Xout[48..42]	= Xoutbuf6[].q;
Xout[41..35]	= Xoutbuf5[].q;
Xout[34..28]	= Xoutbuf4[].q;
Xout[27..21]	= Xoutbuf3[].q;
Xout[20..14]	= Xoutbuf2[].q;
Xout[13..7]		= Xoutbuf1[].q;
Xout[6..0]		= Xoutbuf0[].q;

END;